Dr. Usman's Cardiology Notes

  Classification of Left Atrial (LA) Thrombus Left atrial thrombus is a clinically significant finding, most commonly associated with atrial fibrillation, rheumatic mitral valve disease, and severe left ventricular dysfunction. Proper classification helps guide anticoagulation, cardioversion planning, and interventional strategy. --- 1. Classification Based on Location A. Left Atrial Appendage (LAA) Thrombus Most common site (>90% in non-valvular AF) Best visualized on TEE Often associated with: Atrial fibrillation Low LAA emptying velocity (<20 cm/s) Spontaneous echo contrast (“smoke”) Clinical significance: Contraindication to cardioversion and catheter ablation until resolved. --- B. Left Atrial Body Thrombus Seen in: Rheumatic mitral stenosis Severely dilated LA May be mural or mobile Higher embolic risk if pedunculated or mobile More common in valvular AF compared to non-valvular AF. --- 2. Classification Based on Mobility 1. Mural (Non-mobile) Thrombus Attached along LA...

  Watch the above video for ECG example explained. Premature Ventricular Complexes (PVCs) Arising from the Inferoapical Left Ventricle Premature ventricular complexes (PVCs) originating from the inferoapical left ventricle (LV) represent a less common subset of idiopathic ventricular ectopy. Unlike the more frequent right ventricular outflow tract (RVOT) PVCs, inferoapical LV PVCs arise from the distal inferior wall or apical segments of the LV and have distinct electrocardiographic and mapping characteristics. Recognition of their ECG pattern is essential for: Accurate localization Differentiation from fascicular or papillary muscle PVCs Planning catheter ablation --- Anatomical Substrate The inferoapical LV corresponds to: Distal inferior wall True apex (inferior portion) Region supplied mainly by the posterior descending artery (RCA or LCx depending on dominance) Potential arrhythmogenic substrates: Idiopathic focal automaticity Triggered activity Small areas of fibrosis (post-m...

M-Mode Echocardiography: Normal Values and Key Diagnostic Findings What is M-Mode in Echocardiography? M-Mode (Motion mode) is a one-dimensional echocardiographic technique that records the motion of cardiac structures along a single ultrasound line over time. It provides: Excellent temporal resolution Precise linear measurements Accurate assessment of valve motion LV dimension and wall thickness quantification Although 2D and Doppler imaging are routine, M-mode remains essential for standard chamber measurements and subtle motion abnormalities. --- Standard M-Mode Views 1. Parasternal Long Axis (PLAX) – LV Measurements Cursor placed perpendicular to LV long axis at the level of mitral leaflet tips. Measurements Taken: IVSd (Interventricular septal thickness in diastole) LVIDd (LV internal diameter in diastole) LVIDs (LV internal diameter in systole) LVPWd (Posterior wall thickness in diastole) --- Normal Adult LV M-Mode Values (ASE-Based) LV Dimensions LVIDd Men: 4.2 – 5.8 cm Women: 3...

Rheumatic Heart Disease (RHD) on Echocardiography (Guideline-oriented, practical approach) 1. Mitral Valve – Most Commonly Involved Morphologic Features (Highly Suggestive of Rheumatic Etiology) • Leaflet thickening (≥3 mm at leaflet tip in diastole) • Anterior leaflet doming (“hockey-stick” appearance) • Commissural fusion • Subvalvular thickening and chordal shortening • Restricted posterior leaflet motion Mitral Stenosis (Rheumatic Pattern) • Planimetry: Reduced MVA • Mean gradient elevated • Pressure half time prolonged • Funnel-shaped valve in diastole Rheumatic Mitral Regurgitation • Eccentric MR jet • Leaflet restriction rather than prolapse • Thickened tips with preserved base (early disease) --- 2. Aortic Valve Involvement Typical Features • Cusp thickening • Commissural fusion • Restricted cusp motion • Central AR jet (coaptation defect) Rheumatic AR often coexists with rheumatic MS. --- 3. Multivalvular Disease Pattern (Clue to RHD) • Mitral + Aortic involvement common • Tri...

Rheumatic Mitral Stenosis – Key Echocardiographic Assessment Points 1) Morphologic Features (2D Echo – Parasternal & Apical Views) • Thickened mitral leaflets (especially leaflet tips) • Diastolic doming of anterior leaflet (“hockey stick” appearance) • Commissural fusion (best seen in parasternal short axis) • Reduced leaflet mobility • Subvalvular involvement: chordal thickening, fusion, shortening • Calcification (late disease) Rheumatic MS typically shows leaflet tip restriction with relatively preserved basal leaflet mobility (early disease). --- 2) Mitral Valve Area (MVA) – Severity Assessment • Planimetry (PSAX at leaflet tips in mid-diastole) – Gold standard if image quality good • Pressure Half-Time (PHT method): MVA = 220 / PHT • Continuity equation (if significant MR absent) Severity grading: • Mild: MVA > 1.5 cm² • Moderate: 1.0–1.5 cm² • Severe: < 1.0 cm² • Very severe: ≤ 0.8 cm² Always prefer planimetry when feasible. --- 3) Transmitral Doppler Assessment • Mean...

Mitral Inflow E/A Ratio by Pulsed Wave Doppler A Practical, Guideline-Based Approach --- 1. Introduction Mitral inflow assessment using pulsed wave (PW) Doppler is a fundamental component of diastolic function evaluation. The E/A ratio reflects the relationship between early passive LV filling (E wave) and late filling due to atrial contraction (A wave). It is simple to measure but frequently misinterpreted if age, heart rate, and complementary parameters are not considered. Guidelines reference: ASE/EACVI Recommendations for the Evaluation of LV Diastolic Function (2016 update). --- 2. Physiology Behind E and A Waves During diastole: • Early rapid filling → E wave • Diastasis → minimal flow • Atrial contraction → A wave Normal physiology: Young adults: E > A (E/A > 1) With aging: relaxation slows → E decreases, A increases --- 3. Correct Method of Measuring E/A Ratio A. Image Acquisition View: Apical 4-chamber Doppler type: Pulsed Wave (PW) Sample volume size: 1–3 mm B. Correct ...

Major Echocardiographic Views and Normal Dimensions of the Right Ventricle (RV) and Right Atrium (RA) Right heart assessment is essential in pulmonary hypertension, congenital heart disease, RV infarction, cardiomyopathy, and advanced left-sided heart disease. Accurate chamber quantification should follow the recommendations of the American Society of Echocardiography (ASE) and the European Association of Cardiovascular Imaging (EACVI). Right heart measurements are ideally obtained at end-diastole (for RV size) and end-systole (for RA area), using RV-focused views whenever possible. ━━━━━━━━━━━━━━━━━━ 1. Apical 4-Chamber View (RV-Focused View) This is the most important view for quantitative RV and RA assessment. Technique: • Optimize by centering and enlarging the RV • Avoid LV foreshortening • Measure RV at end-diastole • Measure RA at end-systole Right Ventricle – Normal Dimensions (End-Diastole) • RV Basal Diameter (RVD1): 25–41 mm • RV Mid Cavity Diameter (RVD2): 19–35 mm • RV Lon...

  How to diagnose Dextrocardia on ECG? DEXTROCARDIA – ECG SUMMARY (High-Yield) Classic ECG Findings Limb Leads Lead I: inverted P, QRS, T (often QS) aVR: upright P, QRS, T Inferior leads (II, III, aVF): usually positive Precordial Leads (Left-sided placement) Absent R-wave progression Dominant S waves V1–V6 All QRS predominantly negative Key Concept Electrical forces directed rightward because heart is located on right side. --- Confirmation 1. Apex beat on right side 2. Chest X-ray → right-sided cardiac shadow 3. Repeat ECG with right-sided leads (V1R–V6R) → normal R progression appears --- Differential Diagnosis 1) RA–LA Limb Lead Reversal (Most common mimic) Lead I negative aVR positive BUT normal R-wave progression in chest leads → Chest leads differentiate it --- 2) Extreme Right Axis Deviation Lead I negative Inferior leads may vary Normal precordial progression → Does NOT give global negative V1–V6 --- 3) Severe COPD / Vertical heart Low voltage Delayed R progression Not glo...

 

The most dangerous ECGs don’t always have the biggest ST elevation. If you’re staring at V2–V3 trying to decide between Early Repolarization and a subtle LAD occlusion, stop looking at the ST segment and look at the Terminal QRS. What is Terminal QRS Distortion? It’s a binary finding. In V2 or V3, ask yourself: Is the S-wave gone? Is the J-wave gone? If the answer to both is YES, you are looking at Grade III ischemia. The Stats: Specificity: ~100% vs. Early Repolarization. BER simply doesn’t do this. Sensitivity: ~20–35%. It won’t catch every STEMI, but when it’s there, it’s a “rule-in” sign. Risk: Associated with larger infarct size (CMR-proven) and higher rates of heart failure. The Logic: This is depolarization failing in real-time. Severe ischemia slows conduction so much that the end of the QRS gets “swallowed” by the repolarization phase. Takeaway: Millimeters can lie. Morphology rarely does. If the S-wave is missing in the anterior leads, call the lab.

Assessment of Pulmonary Embolism (PE) Pulmonary embolism (PE) is a potentially life-threatening condition requiring rapid, structured, and guideline-directed evaluation. Early risk stratification determines urgency of imaging, need for thrombolysis, and level of care. This post summarizes a practical, ESC-aligned approach to assessment of PE. 1. Clinical Suspicion Always think of PE in patients with: Acute unexplained dyspnea Pleuritic chest pain Hemoptysis Syncope Unexplained tachycardia New hypoxia Risk Factors Recent surgery or immobilization Active cancer Previous VTE Pregnancy/postpartum OCP use Thrombophilia Obesity 2. Hemodynamic Assessment (First Step) Immediately determine if the patient is: A. Hemodynamically Unstable (High-Risk PE) SBP <90 mmHg Drop in SBP ≥40 mmHg Shock or cardiac arrest → Urgent bedside echocardiography → If RV dysfunction present → treat as high-risk PE (consider thrombolysis) 3. Clinical Probability Assessment Use ...

Dyslipidemia Primary Prevention Guidelines (focusing on preventing first cardiovascular events) 1. Cardiovascular Risk Assessment • All adults should have their ASCVD risk estimated using a validated risk calculator (e.g., ACC/AHA pooled cohort risk score, QRISK3, Framingham Risk Score) to guide prevention strategies. Risk factors include age, sex, blood pressure, smoking, diabetes, lipid levels, family history, and others.  • Reassess risk periodically (e.g., every 4–6 years in adults without disease).  2. Lifestyle Modification (First-Line in All Individuals) • Healthy diet: Emphasize vegetables, fruits, whole grains, lean proteins, legumes, nuts; reduce saturated fat, trans fats and dietary cholesterol.  • Physical activity: ≥150 minutes/week of moderate-intensity or ≥75 minutes/week of vigorous aerobic exercise.  • Weight management: Aim for BMI 18.5–24.9 and waist circumference reduction.  • Smoking cessation and blood pressure/glucose control.  3. Lip...

  Pulmonary Vein (PV) Doppler Patterns – Normal and in Disease Pulmonary vein Doppler is recorded using pulsed-wave Doppler (usually from apical 4-chamber view for right upper PV or by TEE). It reflects left atrial (LA) pressure and compliance, and is essential in diastology and mitral valve assessment. ━━━━━━━━━━━━━━━━━━ 1. Normal Pulmonary Vein Doppler Pattern Normal waveform has three components: 1️⃣ S wave (Systolic forward flow) • Occurs during LV systole • Blood flows from pulmonary veins → LA • Normally S ≥ D in younger adults • Reflects LA relaxation and descent of mitral annulus 2️⃣ D wave (Diastolic forward flow) • Occurs during early LV diastole • Corresponds to mitral E wave • Reflects LA pressure and LV relaxation 3️⃣ Ar wave (Atrial reversal) • Occurs during atrial contraction • Small retrograde flow into pulmonary veins • Normally: Ar velocity < 35 cm/s Ar duration < mitral A duration 👉 Normal Pattern: S wave dominant or equal to D Small Ar reversal ━━━━━━━━━━...

  Congenital AV Block – Pacing Indications Congenital atrioventricular (AV) block may be isolated (often immune-mediated due to maternal anti-Ro/SSA or anti-La antibodies) or associated with structural heart disease (e.g., congenitally corrected TGA). Pacing decisions depend on symptoms, ventricular rate, ventricular function, and risk markers. --- 1. Class I Indications (Permanent Pacemaker Recommended) 1. Symptomatic bradycardia Syncope, presyncope Heart failure Exercise intolerance 2. Asymptomatic complete (3rd-degree) AV block with: Wide QRS escape rhythm Ventricular dysfunction Complex ventricular ectopy Prolonged QT interval 3. Neonates/Infants with complete AV block and: Ventricular rate <55 bpm Ventricular rate <70 bpm if associated with congenital heart disease 4. Postoperative advanced AV block Persisting >7–10 days after congenital cardiac surgery --- 2. Class IIa Indications (Reasonable to Pace) 1. Asymptomatic complete AV block beyond infancy with: Average hea...

Vericiguat in Heart Failure: Mechanism, Evidence, Dosing, and Clinical Positiom Introduction Vericiguat is a novel oral soluble guanylate cyclase (sGC) stimulator approved for patients with symptomatic chronic heart failure with reduced ejection fraction (HFrEF) who have had recent worsening heart failure despite guideline-directed medical therapy (GDMT). It targets the nitric oxide–sGC–cyclic GMP pathway, which is impaired in advanced heart failure. This article provides a clinically focused, guideline-oriented review of vericiguat for practicing physicians and cardiology trainees. --- Pathophysiologic Rationale In chronic HFrEF: Endothelial dysfunction reduces nitric oxide (NO) bioavailability Oxidative stress impairs soluble guanylate cyclase activity Reduced cyclic GMP (cGMP) leads to: Increased vascular tone Myocardial stiffness Fibrosis Progressive ventricular remodeling Vericiguat directly stimulates soluble guanylate cyclase and enhances its sensitivity to endogenous NO, restor...

Comparative Pharmacology of NOACs (DOACs) Non–vitamin K oral anticoagulants (NOACs), also called direct oral anticoagulants (DOACs), include: Dabigatran Rivaroxaban Apixaban Edoxaban They differ in mechanism, pharmacokinetics, renal dependence, drug interactions, and reversal strategies. --- 1. Mechanism of Action Drug Target Site in Coagulation Cascade Dabigatran Direct Thrombin (Factor IIa) inhibitor Final step – prevents fibrin formation Rivaroxaban Direct Factor Xa inhibitor Blocks conversion of prothrombin → thrombin Apixaban Direct Factor Xa inhibitor Same Edoxaban Direct Factor Xa inhibitor Same Key distinction: Dabigatran → Thrombin inhibitor Others → Factor Xa inhibitors --- 2. Pharmacokinetics Comparison Parameter Dabigatran Rivaroxaban Apixaban Edoxaban Bioavailability 6–7% 80–100% (10 mg) ~50% ~62% Tmax 1–3 h 2–4 h 3–4 h 1–2 h Half-life 12–17 h 5–13 h 8–15 h 10–14 h Dosing BID OD (or BID ACS) BID OD Food effect No major Required for 15/20 mg No No Clinical pearl: Rivaroxaba...

ECG Findings of Pulmonary Embolism (PE) 1. Sinus Tachycardia (Most Common Finding) • Most frequent ECG abnormality in acute PE • Heart rate usually >100 bpm • Reflects hypoxia, pain, anxiety, and sympathetic activation --- 2. S1Q3T3 Pattern (McGinn–White Sign) • Deep S wave in Lead I • Q wave in Lead III • T-wave inversion in Lead III • Suggests acute right heart strain • Seen in <20% cases (not sensitive but classic for exams) --- 3. Right Heart Strain Pattern • T-wave inversion in V1–V4 • T-wave inversion in inferior leads (II, III, aVF) • Reflects acute RV pressure overload • Associated with worse prognosis --- 4. Right Bundle Branch Block (RBBB) • Incomplete or complete RBBB • rSR′ pattern in V1 • Wide QRS if complete (>120 ms) • Caused by acute RV dilation --- 5. Right Axis Deviation • QRS axis > +90° • Dominant R wave in lead III • Reflects RV strain --- 6. P Pulmonale (Right Atrial Enlargement) • Tall peaked P wave (>2.5 mm) in lead II • Indicates acute right atri...

Narrow QRS Tachycardia: Differential Diagnosis  Narrow QRS Tachycardia: Differential Diagnosis Comprehensive Clinical & ECG-Based Approach Introduction Narrow QRS tachycardia is one of the most frequently encountered arrhythmias in emergency rooms, CCUs, and electrophysiology labs. A narrow complex (QRS < 120 ms) indicates that ventricular activation is occurring through the normal His–Purkinje system. Therefore, the arrhythmia origin is either: • Supraventricular (atria or AV junction) • Ventricular but conducting normally via the conduction system (rare) Correct diagnosis is critical because management differs dramatically between sinus tachycardia, atrial tachyarrhythmias, and AV reentrant tachycardias. --- Definition Narrow QRS Tachycardia = Heart rate >100 bpm QRS duration <120 ms --- Stepwise Clinical Approach Before jumping to labels, always analyze systematically: 1. Is it regular or irregular? 2. Are P waves visible? 3. What is the RP interval? 4. Is there AV ...

NOACs Dosing and Reversal A Practical, Guideline-Based Clinical Guide Introduction Non–vitamin K oral anticoagulants (NOACs), also called direct oral anticoagulants (DOACs), have largely replaced warfarin in many clinical settings due to predictable pharmacokinetics, fewer interactions, and no routine INR monitoring requirement. Commonly used NOACs include: Dabigatran Rivaroxaban Apixaban Edoxaban --- Mechanism of Action Drug Target Dabigatran Direct thrombin (Factor IIa) inhibitor Rivaroxaban Factor Xa inhibitor Apixaban Factor Xa inhibitor Edoxaban Factor Xa inhibitor --- Indications 1. Non-valvular atrial fibrillation (stroke prevention) 2. Treatment of DVT 3. Treatment of PE 4. Secondary prevention of VTE 5. Post-orthopedic surgery thromboprophylaxis --- Standard Dosing 1. Stroke Prevention in Atrial Fibrillation Dabigatran 150 mg twice daily 110 mg twice daily (elderly/high bleeding risk) Rivaroxaban 20 mg once daily (with food) 15 mg once daily if CrCl 15–49 mL/min Apixaban 5 mg ...